Method and system for non-destructive metrology of thin layers

Abstract

A monitoring system and method are provided for determining at least one property of an integrated circuit (IC) comprising a multi-layer structure formed by at least a layer on top of an underlayer. The monitoring system receives measured data comprising data indicative of optical measurements performed on the IC, data indicative of x-ray photoelectron spectroscopy (XPS) measurements performed on the IC and data indicative of x-ray fluorescence spectroscopy (XRF) measurements performed on the IC. An optical data analyzer module analyzes the data indicative of the optical measurements and generates geometrical data indicative of one or more geometrical parameters of the multi-layer structure formed by at least the layer on top of the underlayer. An XPS data analyzer module analyzes the data indicative of the XPS measurements and generates geometrical and material related data indicative of geometrical and material composition parameters for said layer and data indicative of material composition of the underlayer. An XRF data analyzer module analyzes the data indicative of the XRF measurements and generates data indicative of amount of a predetermined material composition in the multi-layer structure. A data interpretation module generates combined data received from analyzer modules and processes the combined data and determines the at least one property of at least one layer of the multi-layer structure.

1 . A monitoring system for determining at least one property of an integrated circuit (IC) comprising a multi-layer structure formed by at least a layer on top of an underlayer, the system comprising a computer system comprising data input and output utilities, a memory utility, and a data processor and analyzer utility, wherein:
 said data input utility is configured to receive measured data comprising data indicative of optical measurements performed on said IC, data indicative of x-ray photoelectron spectroscopy (XPS) measurements performed on said IC and data indicative of x-ray fluorescence spectroscopy (XRF) measurements performed on said IC;   said data processor and analyzer utility comprising:
 an optical data analyzer module configured and operable to analyze said data indicative of the optical measurements and generate geometrical data indicative of one or more geometrical parameters of the multi-layer structure formed by at least the layer on top of the underlayer, 
 an XPS data analyzer module configured and operable to analyze the data indicative of the XPS measurements and generate geometrical and material related data indicative of geometrical and material composition parameters for said layer and data indicative of material composition of the underlayer; 
 an XRF data analyzer module configured and operable to analyze the data indicative of the XRF measurements and generate data indicative of amount of a predetermined material composition in the multi-layer structure; and 
 a data interpretation module configured and operable for data communication with the optical data analyzer, the XPS data analyzer and the XRF data analyzer modules to generate combined data received from said modules and process the combined data and determine said at least one property of at least one layer of multi-layer structure. 
   
     
     
         2 . The system of  claim 1 , wherein said data interpretation module is configured and operable to utilize said geometrical data of the multi-layer structure and perform data interpretation of the geometrical and material related data and said data indicative of the amount of the predetermined material composition in the multi-layer structure. 
     
     
         3 . The system of  claim 2 , wherein each of the analyzer modules is configured and operable to process the data indicative of the respective measurements by applying to said data a fitting procedure using one or more data interpretation models. 
     
     
         4 . The system of  claim 3 , wherein the data interpretation module is configured and operable to perform mutual optimization of the data interpretation models used by the analyzer modules by injecting one or more of geometrical and material composition relating parameters obtained from one of the fitting procedures performed by one of the analyzer modules using the respective data interpretation model into at least one of the other data interpretation models. 
     
     
         5 . The system of  claim 1 , wherein said data indicative of optical measurements comprises optical critical dimensions relating data. 
     
     
         6 . The system of  claim 1 , wherein said geometrical data generated by the optical data analyzer module comprises at least thickness parameter of the multi-layer structure. 
     
     
         7 . The system of  claim 1 , wherein said geometrical data generated by the XPS data analyzer module comprises a thickness of said layer, and the material composition related data comprises the material composition of said layer and a percentage content of said predetermined material composition in the underlayer. 
     
     
         8 . The system of  claim 6 , wherein said geometrical data generated by the XPS data analyzer module comprises a thickness of said layer, and the material composition related data comprises the material composition of said layer and a percentage content of said predetermined material composition in the underlayer. 
     
     
         9 . The system of  claim 1 , wherein said computer system is configured for data communication, via a communication network, with one or more measured data providers to receive said measured data. 
     
     
         10 . The system of  claim 9 , wherein said one or more measured data providers comprise at least one storage device in which said measured data is stored and to which the computer system has access via the communication network. 
     
     
         11 . The system of  claim 9 , wherein said one or more measured data providers comprises at least one measurement tool configured to perform the respective measurements and collect the measured data. 
     
     
         12 . The system of  claim 1 , wherein said computer system is integral with a measurement tool providing one of said data indicative of optical measurements, said data indicative of XPS measurements and said data indicative of XRF measurements, and is configured for data communication, via a communication network, with one or more measured data providers to receive other measured data from said data indicative of optical measurements, said data indicative of XPS measurements and said data indicative of XRF measurements. 
     
     
         13 . The system of  claim 12 , wherein said one or more measured data providers comprises at least one measurement tool configured to perform the respective measurements. 
     
     
         14 . A hybrid metrology system configured for determining at least one property of an integrated circuit (IC) comprising a multi-layer structure formed by at least a layer on top of an underlayer, the hybrid metrology system comprising:
 a measurement system comprising: an optical measurement tool configured for performing optical critical dimension (OCD) measurements on the IC and generating optical measured data; an x-ray photoelectron spectroscopy (XPS) measurement tool for performing measurements on said IC and generating XPS measured data; and an x-ray fluorescence spectroscopy (XRF) measurement tool configured to perform XRF measurements on said IC and generate XRF measured data; and   the monitoring system of  claim 1  for receiving and processing the measured data.   
     
     
         15 . A method for use in determining property of an integrated circuit (IC) comprising a multi-layer eSiGe structure formed by at least a Si-cap layer on top of SiGe layers, the method being carried out by a computer system comprising data input and output utilities, a memory utility, and a data processor and analyzer utility, the method comprising:
 providing and storing in the memory utility measured data comprising first data indicative of optical critical dimension (OCD) measurements performed on said structure, second data indicative of x-ray photoelectron spectroscopy (XPS) measurements performed on said structure, and third data indicative of x-ray fluorescence spectroscopy (XRF) measurements performed on said structure;   processing the measured data by said processing and analyzing utility, said processing comprising:
 analyzing the first OCD data by applying thereto model-based processing using one or more data interpretation models, and generating geometrical data indicative of at least thickness of the multi-layer structure, 
 analyzing the second, XPS data by applying thereto model-based processing using one or more data interpretation models, and generating geometrical and material related data indicative of at least thickness of the Si-cap layer percentage contents of Ge in SiGe layers; 
 analyzing the third, XRF data by applying thereto model-based processing using one or more data interpretation models, and generating data indicative of amount of Ge material in said structure; and 
 generating and interpreting combined data formed by the geometrical data and the material data and determining the properties of the structure comprising at least the thickness of the SiGe layers. 
   
     
     
         16 . The method of  claim 15 , wherein said interpreting of the combined data comprises utilizing the thickness of the structure obtained from model-based processing of the OCD measured data and performing data interpretation of the geometrical and material data. 
     
     
         17 . The method of  claim 15 , wherein said interpreting of the combined data comprises performing mutual optimization of the data interpretation models by injecting one or more of the geometrical and material relating parameters obtained from one of the model-based processing using the respective data interpretation model into at least one of the other data interpretation models.